Open AccessEnhanced performance of N-polar AlGaN-based deep-ultraviolet light-emitting diodes
Author(s) -
Zhe Zhuang,
Daisuke Iida,
Kazuhiro Ohkawa
Publication year - 2020
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.403168
Subject(s) - light emitting diode , materials science , optoelectronics , quantum efficiency , ultraviolet , diode , voltage droop , polar , quantum well , optics , laser , physics , voltage , quantum mechanics , astronomy , voltage divider
We numerically investigated the performance of N-polar AlGaN-based ultraviolet (UV) light-emitting diodes (LEDs) with different Al contents in quantum wells (QWs) and barriers. We found that N-polar structures could improve the maximum internal quantum efficiency (IQE) and suppress the efficiency droop, especially for deep-UV LEDs. Compared to metal-polar LEDs, N-polar ones retained higher IQE values even when the acceptor concentrations in the p-layers were one order of magnitude lower. The enhanced performance originated from the higher injection efficiencies of N-polar structures in terms of efficient carrier injection into QWs and suppressed electron overflow at high current densities.